﻿/**
 * Copyright (c) 2011-2016, Mobangjack 莫帮杰 (mobangjack@foxmail.com).
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace util.src
{
    class SequencedFIFO<T> : IFIFO<T>
    {
        private T[] array;
        private int r;
        private int w;

        public SequencedFIFO(int initialCapacity)
        {
            array = new T[initialCapacity];
            r = w = 0;
        }

        public void Put(T item)
        {
            Arr<T>.DoubleSizeOnThreshold(array, w);
            array[w++] = item;
        }

        public T Get()
        {
            return array[r++];
        }

        public T PreRead()
        {
            return array[r];
        }

        public int Count()
        {
            return w - r;
        }

        public int Capacity()
        {
            return array.Length;
        }
    }
}
